<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>容器练习</title>
<style>
*{padding: 0;margin:0;}
#wrap{
    width: 1000px;
    height: 500px;
    background: skyblue;
    margin:50px auto;
    display: -webkit-flex;
    /* flex-direction: row; */
    /* flex-direction: column; */
    /* flex-direction: row-reverse; */
    /* flex-direction: column-reverse; */
    /* justify-content: flex-end; */
    /* justify-content: center; */
    /* justify-content: space-between; */
    /* align-items: flex-end */
    /* align-items:flex-start; */
    /* align-items: center; */
    /* align-items: stretch; */
    /* flex-wrap: nowrap; */
    flex-wrap: wrap;
    /* flex-wrap: wrap-reverse; */
    /* flex-flow: column-reverse; */
    align-content: flex-start;
    /* align-content: flex-end; */
    /* align-content: center; */


}
#box1{
    background: pink;
    /* flex-grow: 1; */
    /* width: 500px; */
}
#box2{
    background: red;
    /* flex-grow: 1; */
    /* width: 500px; */
}
#box3{
    background: olive;
    /* flex-grow: 1; */
    /* width: 500px; */
}
</style>    
</head>
<body>
    <div id="wrap">
        <div id="box1">1111</div>
        <div id="box2">2222</div>
        <div id="box3">3333</div>
    </div>   
</body>
</html>